Feeder bar for feeding sheets of cardboard or the like



Feb. 6, 1951 W. E. BOWERSOCK FEEDER BAR FOR FEEDING SHEETS OF CARDBOARDOR THE LIKE Filed March 13, 1948 IN V EN TOR.

W/LBER BOWERSOGK HIS A TTOR/VEY Patented Feb. 6, 1951 OFFICE FEEDER BARFOR FEEDING SHEETS OF CARDBOARD OR THE LIKE Wilber E. Bowersock,Rochester, N. Y.

Application March 13, 1948, Serial No. 14,656

Claims. 1

This invention relates to feeder bars, and, more particularly, to thevariety adapted for feeding the lowermost sheet or blank of cardboard orthe like from a quantity thereof stacked in a hopper, of a box blankfolding machine, for example, one object of the invention being toprovide an improved feeder bar of this type having a constructioncapable of operating in a more efficient and reliable manner.

Such feeder bars require a minimum thickness in order to insuresufficient strength and rigidity. On the other hand, they are subject toemployment for feeding relatively thin sheets and it not infrequentlyhappens that such sheets, particularly of the corrugated board variety,are inadvertenty crushed at their edge portion, so as to materiallyreduce their thickness at such an edge. As a, result, it commonlyhappens that the ordinary feeder bar overlaps and feeds two sheets orblanks at a time, which jam or even injure mechanism, so as to recuirestoppage of the machine for clearing it of spoiled blanks or adjustingor repairing its parts. Another object, therefore, is to provide afeeder bar of substantial thickness and "strength in a form ofconstruction adapted for feeding blanks of minimum thickness, equal toor less than the thickness or height of the bar itself, in a reliablemanner, one at a time, so as to avoid interference with the operation ofthe machine.

To these and other ends, the invention resides in certain improvementsand combinations of parts, all as will be hereinafter more fullydescribed, the novehfeatures being pointed out in the claims at the endof the specification.

In the drawings:

Fig. 1 is a perspective view of a gripper bar embodying the presentinvention;

i Fig. 2 is an enlarged, transverse,.sectiona1 elevation of the barbolted to a feed plate and showing the same about to feed a blank havinga thickness substantially equal to that of the bar;

Fig. 3 is a view similar to Fig. 2, but showing the blank being fed bythe bar;

Fig. 4 is a view similar to Fig. 2, but showing the bar about to feed ablank of substantially less thickness than that of the bar, and

Fig.1?) is a view similar to Fig.4, but showing the blank being fed bythe bar.

The embodiment of the invention at present preferred and hereindisclosed, by way of illustration, comprises a feed bar I0 made ofcarbon steel and of substantially minimum thickness or height of, say,0.100 of an inch": Such a bar is transversely of the usual feed plate[3, which is reciprocated by any suitabe means (not shown) beneath astack of blanks in a hopper of a blanlr feeding machine, for feeding thebottom blank forwardly at each forward reciprocation of the feed plate,as well understood in the art.

The feed bar of the present invention is formed at its forward side withan upright or vertical feeding shoulder i5, preferably of the sameheight as the bar, as shown, and extending continuously from end to end,except as interrupted by a series of pointed teeth I 6 extendingforwardly from the bar and spaced from each other longitudinallythereof, for penetrating the edge of the sheet to be fed and elevatingthe superposed sheets, as hereafter described.

Each tooth i6 is formed by opposite side and top and bottom surfacesconverging to a point,

as shown. The opposite side surfaces I1 and I8 preferably converge atequal angles of inclination with the feed shoulder l5, while the underor bottom surface 19 of the tooth lies in a plane spaced above andparallel with the bottom surface 28 of the feed bar. This under surfacel9, containing the tooth point 2|, is spaced above the. bottom of thebar and the upper surface of the feed plate by a distance which is nogreater than the minimum height or thickness of the edge of the board tobe fed in a state of maximum crushing. In other words, the point of thetooth. is disposed at such a distance above the feed plate that thepoint will always penetrate the sheet in or below the upper surfacethereof, in

any condition of crushing to which it is likely tobe subjected, so as toengage only'the lower sheet and pass under the next sheet above. Thisdistance in the present embodiment, for example,

is 0.640 of an inch.

The upper surface 22 of the tooth is inclined from its point upwardlyand rearwardly to an interrection with the top surface of the bar in aline 23 spacxl somewhat forwardly of the feed tom facing sheets, 25 and26, respectively, while the edge of the board is engaged by the feedshoulder l5, so that the lower board only is fed forwardly from beneaththe stack, as shown. If the edge of the board is presented in crushedcondition, its upper surface will be level with or above the points 2|of the teeth of the feed bar, so that the tooth point will pass underthe superposed board and .cam it, together with the 'whole stack,upwardly to position to be cleared by the top of the feed bar.

The same feed bar is shown in Fig. 4 in position for feeding a blank 2'!having-a thickness or height substantially less than that of thefeed-bar but greater than the height of the point of the bar above thefeed plate, so that when the feed bar is advanced, as shown in Fig. 5,the tooth again penetrates between the top and bottom liners of thelower blank only. The portion of the blank, however, immediately abovethe tooth, is' cammed upwardly by :its inclined upper face 22 raises"also the superposed blanks of the stack, so that as -the lower blank(only is advanced, the feed bar clears and passes under the superposedblank with'out feeding it. The blank is shown with a normal edge, but itis evident that if its edge were crushed to the maximum extent permittedby'the thickness of its componentmateria ls, its top surface would stilllie level with or above :the point of the tooth, and the latter wouldpenetrate and feed the lower blank only and pass under the superposedblank.

"The disclosure therein of particular dimensions of the bar is intendedin a merely illustrative way, as it is obviousthat the same advantageousprinciples may 'beappliedto a series of bars ranging in size inaccordance with the thickness of the sheets to be fed. :It is evidentthat the princip'les of construction herein disclosed provid: a barwhich can be made in the thickness required for strength and rigidity,while being adapted to feed blanks having an edge thickness substanti-Jlessthat the thickness of the bar, the blanks being fed one at a time,in a reliable manner, so as to avoid interruption in the operation of'th: blank folding or other machine with which the feeder bar isassociated.

' It will thus be seen that the invention accomplishesiits objects and'while it has been herein disclosed by reference to the details of apreferre'd embodiment, it is to be understood that such disclosure isintended in an illustrative, rather than a limiting sense, as it iscontemplated that various modifications in the construction andarrangement :of the parts will readily occur 7 said bar having on theside thereof lying in the direction of feed an upright feeding shoulderfor engagement with the edge of a bottom sheet to be fed and having atsaid shoulder a series of pointed teeth extending forwardly in thedirection of feed and spaced longitudinally along said bar, the pointsof said teeth being arranged at a height intermediate the top and bottomof said barand of said sheet to be fed and the upper surfaces of saidteeth being inclined upwardly and rearwardly to a height at least equalto that of said shoulder for raising the superposed sheets to enablesaid :bar to clear and pass under the same and thereby feed singlesheets having a thickness equal to or less than that of said bar.

2. A feeder bar as specified in claim 1 in which *said upper surfaces ofsaid teeth are inclined upwardly and oppositely to the direction of feedto a height equal to that of said shoulder at a line spaced in advanceof the line of said shoulder. 3.. nifeeder bar :as specified in claim 2in which he :under surfaces of said teeth lie in a plane passingsubstantially through the points thereof and above and parallel with thebottom surface of said bar.

i. A feeder bar as specified in claim 3 in which said shoulder issubstantially equal in height to the height of said bar.

5. A feed r bar adapted to be reciprocated for feeding sheets ofcorrugated cardboard and the like singly from the bottom of .a stackthereofi. said bar having on the side thereof lying in the direction offeed a yerticalifeeding shoulder substantially equal in height to saidbar for engagement with the ed e of a bottom sheet to be fed and havinga series of pointed teeth extending forwardly in the direction of feedfrom the upper portion of said shoulder and spaced from one anotherlongitudinally of said bar, the points of said teeth being arranged at aheight less than :at of said bar and intermediate the top and bottom ofsaid sheet to be fed, said teeth having their uppzr surfaces inclinedupwardly and rearwardly to a height equal to that of saidshoulder 1' ata line sr'aced'forwardly in advance of the forthrough the points thereofand above and parallel with the bottom surface of said bar.

WILB'ER E. BOWERSOCK.

REFERENCES CITE-D The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 551,453 Crowell Dec. 17,18951,150,210 Langston Aug. 17,1915 11,592,367 .Hren et al. July 13,19262,158,5G5 Horgan May 16,1989'

